Electronic thermometer with selectable modes

ABSTRACT

An electronic thermometer is configured for selectable predictive modes based upon the same predictive algorithm. A mode selector is adapted for user selection between several modes of operation of the thermometer. Each mode of operation utilizes the same predictive algorithm for estimating the temperature of the subject before the thermometer reaches full equilibrium. Different modes offer users a selection for striking the appropriate balance between response time and precision, based upon user preferences and needs.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a divisional of and claims the benefit of priorityunder 35 U.S.C. §120 to co-pending U.S. patent application Ser. No.12/463,767, filed May 11, 2009, which is a continuation of and claimsthe benefit of priority under 35 U.S.C. §120 to U.S. patent applicationSer. No. 11/539,438 (now U.S. Pat. No. 7,549,792), filed Oct. 6, 2006,each of which is incorporated herein by reference in its entirety forall purposes.

BACKGROUND

Aspects of the invention pertain generally to the field of electronicthermometers and more particularly to the field of fast responseelectronic thermometers employing a sensor probe.

Electronic thermometers are widely used in the healthcare field formeasuring patient's body temperature. Typical electronic thermometershave the form of a probe with an elongated shaft portion. Electronictemperature sensors such as thermistors or other temperature-sensitiveelements are contained within the shaft portion. Additional electronicsconnected to the electronic sensor components may be contained within abase unit connected by wire to the shaft portion or may be containedwithin a handle of the shaft portion, for example. Electronic componentsreceive input from the sensor components to compute the patient'stemperature. The temperature is then typically displayed on a visualoutput device such as a seven, or fourteen, segment numerical displaydevice. Additional features of known electronic thermometers includeaudible temperature level notification such as a beep or tone alertsignal. A disposable cover or sheath is typically fitted over the shaftportion and disposed after each use of the thermometer for sanitaryreasons.

Electronic thermometers have many advantages over conventionalthermometers and have widely replaced the use of conventional glassthermometers in the healthcare field. For example, electronicthermometers do not require costly sterilization procedures and do notpresent the dangers associated with mercury or broken glass causinginjury to a patient. Furthermore, electronic thermometers generally havea faster response time than glass thermometers and provide very preciseand accurate temperature measurement information.

Despite the response time improvements over glass thermometers, someknown electronic thermometers have unacceptably long response time. Thelong response time is primarily due to the thermal mass of the probetogether with the sensor components. The thermal mass of the probe andthe sensor components may take several minutes to reach the actual bodytemperature of the patient being measured. The thermal mass of the probetypically begins a measurement cycle at a lower temperature than thepatient being measured and absorbs heat from the patient until thepatient and the thermal mass of the probe reach thermal equilibrium.Therefore, the thermal mass of the probe prevents the sensor temperaturefrom instantaneously reaching a patients body temperature.

Electronic thermometers in the art are known having improved responsetimes that are achieved using a number of different techniques. Onetechnique known in the art employs thermally conductive material such asmetal in the probe tip between the patient contact area and thetemperature sensor. Another technique uses a very thin layer of materialbetween the patient contact area and the temperature sensors. Both ofthese techniques improve response time somewhat but still allow time tobe wasted while heat from the patient flows to the thermal mass of theprobe instead of the temperature sensors.

Previously known electronic thermometers have employed electric heaterelements in the probe shaft to bring the temperature of the thermal massof the probe shaft and probe tip closer to the temperature of thepatient prior to taking temperature measurements. Temperature sensorreadings are used in known methods to control electric current to theheater element. Time is saved because less heat must be transferred fromthe patient to the thermal mass of the probe before the temperaturesensors reach thermal equilibrium with the patient.

The response time of electronic thermometers has also been improved bymethods that do not involve heating the probe shaft or tip. Predictivetype thermometers are known for example, wherein a set of earlytemperature measurements are read by the electronics of the thermometerand a mathematical algorithm is applied to extrapolate to a finalestimated equilibrium temperature. Various prediction type thermometersare known which improve response time and provide accurate temperatureestimations. Still other methods of improving the response time ofelectronic thermometers are known which combine heating methods withprediction methods. For example, one predictive-type clinicalthermometer automatically switches between a plurality of predictionfunctions to determine a final predicted temperature. The thermometermonitors the measured results of the thermometer for a set time beforeapplying an initial predictive function to the measured results. Thethermometer then monitors the ability of the initial predictive functionto predict the measured results. Where the measured temperature resultsdo not follow the initially applied prediction function, the thermometerautomatically selects another prediction function. Again, thethermometer monitors the ability of this other prediction function topredict the measured results. This process of monitoring and switchingto another of a plurality of predictive functions continues until thethermometer determines that a satisfactory prediction is achieved orthat a time limit is reached. In other words, without user input orcontrol, the thermometer can select to apply several differentpredictive functions throughout a single measurement process. Thisautomatic switching from one predictive function to another can addmeasurement time and ignores any user preference or input regardingdesirable prediction time or required accuracy.

Disadvantages of known thermometers leave room for improvement. Forexample, some thermometers still suffer from relatively long responsetimes, as judged by the user of the thermometer. For predictionalgorithms, the goal of decreased response time opposes the goal ofincreased precision. As response time is reduced, precision decreases,and vice versa. Thus, known thermometer designers have had to make adesign choice for the user, constructing thermometers that compromisebetween decreased response time and increased precision. The problemwith making such a choice for all applications, however, is thatdifferent thermometer applications may have different requirements andgoals. For example, some applications require a very short responsetime, but do not require an extremely high level of precision. Incontrast, other applications do not require a short response time, butdo require an extremely high level of precision. Conventionalthermometers ignore these user preferences and may spend more time thana user would prefer obtaining a predicted temperature. Conversely, aconventional thermometer may not spend adequate time determining apredicted temperature of sufficient accuracy. A thermometer that allowedthe user to determine and adjust the balance between response time andprecision based upon the thermometer application would be useful.

SUMMARY

A prediction type electronic thermometer embodying aspects of theinvention is configured to allow user selection of the desired responsetime of the thermometer and the desired precision of the temperaturereadings. In one exemplary embodiment of the present invention, theapplication of a particular prediction algorithm provides a user withcontrol over the desired precision and the thermometer response time. Auser may select how the data collected by the electronic thermometer isapplied to the prediction algorithm, thereby selecting where thecompromise between the countervailing goals of increased precision andreduced response time is maintained.

In one aspect, an electronic thermometer comprises a probe adapted to beheated by a subject for use in measuring the temperature of the subject.The electronic thermometer also comprises at least one temperaturesensor for detecting the temperature of the probe. The electronicthermometer further comprises a processor configured for user selectionbetween at least a first predictive mode of operation of the thermometerand a second predictive mode of operation of the thermometer. In thesecond mode, the thermometer determines temperature more slowly but withgreater precision as compared with the first mode. The first mode ofoperation utilizes the predictive algorithm for estimating thetemperature of the subject before the thermometer reaches fullequilibrium with the subject based on a plurality of samples of thetemperature of the probe detected by the temperature sensor. The secondmode of operation utilizes the same predictive algorithm for estimatingthe temperature of the subject before the thermometer reaches fullequilibrium with the subject based on the plurality of samples of thetemperature of the probe detected by the temperature sensor and anadditional plurality of samples of the temperature of the probe detectedby the temperature sensor.

In another aspect, a method for determining the temperature of a subjectwith an electronic thermometer is disclosed. The method comprisesreceiving from a user of the electronic thermometer a selection betweenat least a first mode of operation of the thermometer and a second modeof operation of the thermometer. The method further comprises collectingtemperatures of the subject measured by the thermometer over time andapplying a first portion of the collected measured temperatures to apredictive algorithm according to the first mode of operation, when theselection received from the user is for a first mode of operation. Themethod further comprises applying the first portion and a second portionof the collected measured temperatures to the same predictive algorithmaccording to the second mode of operation, different from the first modeof operation, when the selection received from the user is for a secondmode of operation. The method further comprises estimating thetemperature of the subject with the predictive algorithm based upon theselected mode of operation before the electronic thermometer reachesequilibrium with the temperature of the subject.

In still another aspect, a method for determining the temperature of asubject with an electronic thermometer comprises receiving from a userof the electronic thermometer a selection of one of a plurality ofpredictive modes of operation of the thermometer. The plurality ofpredictive modes of operation are selectable along a continuum from ashortest measurement duration and a standard-precision measurement to alongest measurement duration and a highest-precision measurement. Themethod further comprises collecting temperatures of the subject measuredby the thermometer over time and applying at least some of the collectedmeasured temperatures to a predictive algorithm determined according tothe predictive mode of operation selected by the user, where a fewernumber of the collected measured temperatures are applied to thepredictive algorithm for standard-precision measurement than for thehighest-precision measurement. The method further comprises estimatingthe temperature of the subject with the predictive algorithm based uponthe selected predictive mode of operation.

Other exemplary features will be in part apparent and in part pointedout hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective of an electronic thermometer of one embodimentof the invention;

FIG. 2 is a perspective of a probe of the electronic thermometer of FIG.1;

FIG. 3 is an exemplary display of the electronic thermometer of FIG. 1;and

FIG. 4 is a flow diagram of a method of one embodiment of the invention.

Corresponding reference characters indicate corresponding partsthroughout the several views of the drawings.

DETAILED DESCRIPTION

Referring now to the drawings and in particular to FIGS. 1 and 2, anelectronic thermometer constructed according to the principles of thepresent invention is indicated generally at 1. The electronicthermometer comprises a temperature calculating unit, indicatedgenerally at 3, that is sized and shaped to be held comfortably in thehand H. The calculating unit 3 (broadly, “a base unit”) is connected bya helical cord 5 to a probe 7 (the reference numerals indicating theirsubjects generally). The probe 7 is constructed for contacting thesubject (e.g., a patient, not shown) and sending signals to thecalculating unit 3 representative of the temperature. The calculatingunit 3 receives the signals from the probe 7 and uses them to calculatethe temperature. Suitable circuitry for performing these calculations iscontained within a housing 9 of the calculating unit 3. The logic in thecircuitry may include a predictive algorithm for rapidly ascertainingthe final temperature of the patient according to two or more modes ofoperation, as will be discussed in greater detail below. The circuitrymakes the calculated temperature appear on a display 11 (e.g., an LCDdisplay) on the front of the housing 9. Other information desirably canappear on the display 11, as will be appreciated by those of ordinaryskill in the art, and discussed in greater detail below with referenceto the display of FIG. 3. A panel 11A of buttons, or other userinterface devices (e.g., switches, toggles, knobs, dials, touch screens,keypads, etc.) for operating the thermometer 1 is located just above thedisplay 11. As would be readily understood by one skilled in the art,other arrangements of the display and panel can be utilized withoutdeparting from the scope of embodiments of the invention.

Referring again to FIGS. 1 and 2, the housing 9 includes a compartment,or slot, (not shown) generally at the rear of the housing that canreceive a distal portion of the probe 7 into the housing for holding theprobe and isolating the distal portion from the environment when not inuse. FIG. 1 illustrates the probe 7 being pulled by the other hand H1from the compartment in preparation for use. The housing 9 also has areceptacle 13 that receives a suitable container, such as a carton C ofprobe covers. In use, the top of the carton C is removed (not shown),exposing open ends of the probe covers. The distal portion of the probe7 can be inserted into the open end of the carton C and one of the probecovers can be captured (e.g., snapped into) an annular recess 14 (FIG.2). Ejection members 15 are located at the junction of a handle 17 ofthe probe 7 with a probe shaft 19. The probe shaft is protected fromcontamination by the cover when the distal portion of the probe shaft 19is inserted, for example, into a patient's mouth. A button 21 on theprobe handle 17 can be depressed to cause the ejection members 15 tomove for releasing the probe cover from the probe shaft 19. Subsequentto use, the probe cover can be discarded. Other ways of capturing andreleasing probe covers may be used without departing from the scope ofthe present invention.

In use, a metal tip 25 (e.g., aluminum) at the distal end of the probeshaft 19 is heated up by the patient and the temperature of the tip isdetected, as will be described more fully hereinafter. The probe coveris preferably made of highly thermally conductive material, at least atits portion covering the tip 25, so that the tip can be rapidly heatedby the patient. The tip 25 also includes a heater element (not shown)used to heat the probe 7 to near the temperature of the patient toprovide a faster response time for the thermometer. One or moretemperature sensors, such as a tip temperature sensor and a proximaltemperature sensor may be disposed within the probe for connection to atemperature prediction component (not shown). In at least oneembodiment, the temperature sensors are connected to a microprocessorsystem which performs the functions of both a heater control circuit anda temperature prediction component. The proximal temperature sensorprovides a signal indicative of the heater temperature for use by theheater control circuit in computing a heater current control value. Theproximal temperature sensor may also provide a signal indicative of theheater temperature for use in a temperature prediction algorithm.

The base unit 3 houses a power supply and electronics for the heatercontrol circuit and the temperature prediction component. The helicalcord 5 carries power from the base unit 3 to the probe 7. While not inuse, the probe 7 may be stored within the slot in the base unit 3. In atleast one embodiment of the invention, the slot may include a switch totrigger initiation of the heater control circuit so that the heaterelement may be powered up beginning when the probe 7 is removed from thebase unit 3. The electronic thermometer 1 also includes a dockingstation 27 for receiving the temperature calculating unit 3, such as forstoring the temperature calculating unit, recharging of the powersupply, establishing communication between the thermometer and thedocking station, and securing the temperature calculating unit, amongothers.

Generally, input from the temperature sensors in the probe 7 is used bya temperature prediction algorithm to determine a predictive temperatureand output the temperature to the display 11. In at least oneembodiment, interim output display signals are continuously updated asthe temperature sensors reach equilibrium. In an alternative embodiment,no output is displayed until after a temperature reading is determinedaccording to a mode of operation selected by the user. The temperatureprediction algorithm monitors the probe 7 temperature in time and thenuses that information to predict the final stabilization temperature.The prediction algorithm can take many forms and may be based upon manyvariables, such as heater temperature, probe tip temperature, probecover temperature, skin temperature, body temperature, tissuecapacitance, cover capacitance, probe tip capacitance, body skinresistance, skin-cover resistance, cover-probe resistance, probe-heaterresistance, and time, among others. As an example of such a predictionalgorithm, Applicants hereby incorporate by reference co-assigned U.S.application Ser. No. 09/893,154, entitled Probe Tip Thermal Isolationand Fast Prediction Algorithm, issued Jan. 4, 2005 as U.S. Pat. No.6,839,651. One skilled in the art would readily understand how to createand implement such a prediction algorithm with reference to theabove-noted application.

Referring again to the panel 11A of the electronic thermometer 1depicted in FIG. 1, one exemplary embodiment of the electronicthermometer also comprises a mode selector 11B adapted for userselection between a first mode of operation of the thermometer and asecond mode of operation of the thermometer. Each of the first andsecond modes of operation utilizes the same predictive algorithm forestimating the temperature of the subject before the thermometer 1reaches full equilibrium with the subject. Generally speaking,prediction algorithms are utilized to achieve a primary goal ofdecreased response time. The goal of decreased response time, however,opposes the goal of increased thermometer precision. Generally, asresponse time is reduced, precision decreases, and vice versa. The firstand second modes discussed herein allow a user to select between thefirst and second modes, which each feature a different balance betweenspeed and precision. In the present example, the thermometer 1determines the temperature in the first mode of operation more quickly,as compared with the second mode of operation. Because the temperatureis determined more quickly, it is also determined with less precision,as compared with the second mode of operation. For particularapplications, however, such a level of precision is sufficient, andpreferable because of the decreased time required to estimate such atemperature.

Referring now to FIG. 3, the exemplary display 11 will be described infurther detail. In the present example, the display 11 of the electronicthermometer 1 comprises a visual indicator 31 indicating the mode ofoperation selected by the user. The visual indicator 31 includes twoportions, a first mode indicator 31A and a second mode indicator 31B.Each of the indicators is represented by a particular icon, indicativeof the type of mode selected by the user. For example, because the firstmode determines the temperature more quickly, the first mode indicator31A is depicted as a rabbit, while the second mode is depicted with noicon. This icon serves as a reminder to the user regarding thecharacteristics of the selected mode. The visual indicator 31 alsoincludes a direct mode indicator 31B for indicating that the thermometeris functioning in the direct mode whereby no prediction algorithm isutilized. The display 11 can include other features, such as a numericdisplay 33 (e.g., a seven, or fourteen-segment display device) fordisplaying temperature, a timer icon display 35 for displaying when apulse timer is being used, a body site icon 37 for displaying thecurrent setting for the portion of the subject being tested, and a probeicon 39 for indicating when a probe cover should be installed orremoved. Other features may be incorporated into the display 11 withoutdeparting from the scope of the embodiments of the present invention.

In still another exemplary embodiment, the mode selector 11B is adaptedfor selecting between a plurality of predictive modes of operation ofthe thermometer 1. As described in greater detail below with respect tothe exemplary methods of the present invention, the plurality ofpredictive modes of operation are arranged for selection along acontinuum from a shortest measurement duration and a standard-precisionmeasurement to a longest measurement duration and a highest-precisionmeasurement. In this manner, manipulation of the mode selector 11B isrelatively straightforward, allowing the user to appreciate that movingone direction on the continuum will lead to shorter measurement durationand average precision, while moving in the opposite direction on thecontinuum will lead to longer measurement duration and higher precision.Each of the plurality of predictive modes of operation utilizes the samepredictive algorithm for estimating the temperature of the subjectbefore the thermometer reaches full equilibrium with the subject. Byapplying different data to the same predictive algorithm, temperatureestimates of varying precision and data collection duration may beachieved. This exemplary embodiment also includes a visual indicatorindicating the mode of operation selected by the user, similar to thevisual indicator 31 of FIG. 3. As would be understood by one skilled inthe art, a visual indicator associated with the present embodiment wouldrequire more than three portions, but could be designed in a similarmanner, demonstrating the continuum described above.

For the present embodiment, the mode selector 11B itself may be formedin a number of different ways. For example, the mode selector 11B maycomprise a rotary dial (not shown) adapted to be rotated to a pluralityof positions corresponding to the plurality of predictive modes ofoperation. In another example, the mode selector 11B may comprise amovable selector (not shown) adapted to be moved to a plurality ofpositions corresponding to the plurality of predictive modes ofoperation. In still another example, the mode selector 11B may comprisea plurality of buttons, each button corresponding to one of theplurality of predictive modes of operation. In any event, any type ofmode selector 11B adapted for selecting each the plurality of predictivemodes may be utilized without departing from the scope of the presentembodiment.

Turning to the embodied method of the present invention, a method fordetermining the temperature of a subject with an electronic thermometer1 utilizing a two-mode thermometer operation is generally depicted as 51in FIG. 4. The method 51 comprises receiving, at 53, from a user of theelectronic thermometer 1 a selection between at least a first mode ofoperation of the thermometer and a second mode of operation of thethermometer. As discussed generally above, the first mode and secondmode of the thermometer apply different collected data to the samepredictive algorithm. Once selected, the method 51 decides, at 55,whether the mode is based upon elapsed collection time or a total numberof data points collected (e.g., the first mode of operation) or is basedupon meeting an enhanced precision determination (e.g., the second modeof operation).

In either mode, the method 51 further comprises collecting, at 57 and59, temperatures of the subject measured by the thermometer over time.The collecting 57, 59 can occur at a constant rate (e.g., each 0.188seconds) or at any number of defined or random intervals, eachassociated with a particular time.

Where the mode selected is based upon elapsed collection time or a totalnumber of data points collected (e.g., the first mode of operation), themethod 51 further applies, at 61, at least some of the collected 57measured temperatures to the predictive algorithm according to the firstmode of operation. Alternately, where the mode selected is not basedupon elapsed collection time or a total number of data points collected(e.g., the first mode of operation), but rather is based upon some othercriteria (e.g., precision of the temperature estimation), the method 51applies, at 63, at least some of the collected 59 measured temperaturesto the same predictive algorithm according to the second mode ofoperation, different from the first mode of operation. The first andsecond modes of operation can differ in any number of ways withoutdeparting from the scope of embodiments of the present invention. In oneexample, the applying 61 at least some of the collected measuredtemperatures to the predictive algorithm according to the first mode ofoperation comprises applying fewer measured temperatures to thepredictive algorithm according to the first mode of operation, ascompared with the number of measured temperatures applied to the samepredictive algorithm according to the second mode of operation. In otherwords, the first mode of operation collects fewer data points, orcollects data for a shorter time, than the second mode of operation.Collecting fewer data points or collecting data over a shorter periodprovides a faster response, while providing adequate precision.Alternately, the second mode functions according to the precision of thepresent prediction, which may provide a response in a suitable, yetlonger, time with enhanced precision.

Continuing with the first mode, the method 51 continues by determining,at 67, if the collection time limit has elapsed or the data point limithas been reached. For example, the method 51 can determine if the methodcollected N number of measured temperatures. In another example, themethod 51 can determine if collection 57 has occurred continuously forat least about S number of seconds. If no is the answer to either ofthese inquiries, the method 51 returns to the collecting 57. But if yes,enough data has been collected or adequate time for data collection haspassed, and the method 51 terminates, or truncates, the collecting 57 oftemperatures and continues with estimating, at 69, the temperature ofthe subject with the predicted algorithm by applying the N number ofcollected measured temperatures or the collected measured temperaturescollected for at least about S number of seconds. In this first mode ofoperation, the predictive algorithm estimates 69 the equilibriumtemperature with the data collected thusfar, without regard for theprecision or accuracy of the estimated temperature. Such an estimate 69is in accordance with instructions from the user in selecting the firstmode of operation. This termination of the collecting 57 process iscounterintuitive, as the conventional wisdom in temperature monitoringis to strive to collect more and more data in a shorter amount of timeto improve both the precision and speed of the measurement. Terminatingthe collection of temperature data and proceeding to estimate thetemperature with only the data collected up to that point in timeprovides a thermometer capable of adequate precision, while providingresults in a very short time period. In other words, by restricting datacollection to a particular length of time, thermometer response time isimproved and thermometer performance is adequate for the associatedapplication. In an alternative embodiment, aspects of the invention mayapply reasonable bounds on the measurements to prevent reporting clearlyerroneous readings. For example, if the truncated prediction yields atemperature measurement less than 60° F. or greater than 120° F., theprediction algorithm evaluates one or more additional data samples andadjusts the predicted measurement accordingly.

In a more specific example, the estimating 69 occurs when at leastfourteen measured temperatures have been collected. Where temperaturemeasurements occur at 0.188 second intervals, the temperature isestimated at about 2.6 seconds. In another specific example, theestimating 69 occurs when temperature measurements have occurredcontinuously for at least about 2.6 seconds. With the temperatureestimate determined, the method displays, at 71, the estimatedtemperature for the user. In one example, the method further sounds analarm (not shown) when displaying 71 the estimated temperature to alertthe user that the displayed temperature meets the criteria of theselected mode of operation.

Returning to the second mode of operation, the method 51 has alreadycollected 59 the temperatures of the subject measured by the thermometerover time and applied 63 the collected measured temperatures to the samepredictive algorithm as the first mode of operation, but according tothe second mode of operation. In particular, the method 51 continues byestimating, at 75, the temperature of the subject according to thesecond mode of operation. The method 51 continues by determining, at 77,if these temperature estimates meet the precision requirements of thesecond mode of operation. In one example, the estimate of the predictivealgorithm must converge to a precision meeting a minimum threshold. Forexample, final temperature estimates are calculated according to thetemperature prediction algorithm, including determining a goodnesscriterion.

If the goodness criterion indicates that the prediction is acceptablyprecise, then the thermometer 1 displays 71 the estimated temperature.Alternately, if the goodness criterion indicates that the prediction isnot acceptably precise, then the heating element continues to receivepower, the temperature sensors continue to collect data, and thethermometer 1 returns to collecting 59 more data. Utilizing such apredictive algorithm in the second mode of operation, a time of about 4to 11 seconds is needed to present a final prediction of temperature.Depending upon particular variables, the appropriate prediction time mayrange from 3.2 seconds to about 30 seconds. As an example of such aprediction algorithm utilizing a goodness criteria, Applicants herebyreference co-assigned U.S. application Ser. No. 09/893,154, entitledProbe Tip Thermal Isolation and Fast Prediction Algorithm, issued Jan.4, 2005 as U.S. Pat. No. 6,839,651.

In addition to the first and second modes discussed above, the method 51also contemplates an additional direct mode that may be invokedmanually, such as by user selection, or automatically, such as when thepredictive mode is unable to provide an acceptable estimate within aspecified time period. As shown in FIG. 4, if the goodness criterionindicates that the prediction is not acceptably precise, the method 51does not automatically return to collecting 59 more data. Instead, themethod 51 determines, at 81, if a prediction time limit has elapsed.Where the time limit has not elapsed, the method returns to thecollecting 59, applying 63, estimating 75, and determining 77 tocontinue seeking an estimated temperature meeting the precisionrequirements. Where the time limit has elapsed, the method 51 switches,at 85, to a direct mode of operation. The direct mode collects, at 87,temperature data and determines, at 89, if the collected readings meetthe requirements of the direct mode of operation. In one example, thedirect mode does not apply the predictive algorithm, but simply collectstemperature information until the temperature equilibrates with thesubject. This method is highly accurate, but can take significant time,as the probe 7 must completely equilibrate to the subject.

A short summary comparison of the first and second modes follows.Utilizing the same prediction algorithm, estimating the temperature ofthe subject based upon the first mode of operation occurs more quickly,as compared with the second mode of operation. Put another way,estimating the temperature of the subject with the predictive algorithmbased upon the second mode of operation occurs with greater precision,as compared with the first mode of operation.

These methods are applicable to collecting temperatures of a subject andestimating the temperature of a subject. As would be understood by oneskilled in the art, these methods are readily applicable to collectingtemperatures of a patient measured by the thermometer over time andestimating the temperature of the patient with the predictive algorithmbased upon the selected mode of operation. Other subjects, such asanimals, test apparatus, and other devices requiring measurement mayalso be subject to the disclosed methods without departing from thescope of embodiments of the invention.

Embodiments of the present invention further contemplate a methodincluding a plurality of predictive modes. Where similarities existbetween this method and the previously described method, references willbe made to FIG. 4. Such a method comprises receiving 53 from a user ofthe electronic thermometer 1 a selection of one of a plurality ofpredictive modes of operation of the thermometer. The plurality ofpredictive modes of operation are arranged for selection along acontinuum from a shortest measurement duration and a standard-precisionmeasurement to a longest measurement duration and a highest-precisionmeasurement. In this manner, the continuum allows the user to readilyappreciate that moving one direction on the continuum will lead toshorter measurement duration and average-precision, while moving in theopposite direction on the continuum will lead to longer measurementduration and higher-precision. Each of the plurality of predictive modesof operation utilizes the same predictive algorithm for estimating thetemperature of the subject before the thermometer reaches fullequilibrium with the subject. By applying different data to the samepredictive algorithm, temperature estimates of varying precision anddata collection duration may be achieved.

As with the previously described method, the present method furthercomprises collecting 57 temperatures of the subject measured by thethermometer over time and applying 61 at least some of the collectedmeasured temperatures to a predictive algorithm according to thepredictive mode of operation selected by the user. In other words, thismethod includes several first modes of operation as defined by theprevious method 21. The decision box 55 of FIG. 4 would thereforeinclude additional collecting 57, applying 61, and determining 67 pathsin parallel with the path depicted in FIG. 4. Each alternate path wouldcorrespond to a different mode having a different elapsed time limit ordifferent data point limit than the remaining modes of operation. Themethod further comprises estimating 69 the temperature of the subjectwith the predictive algorithm based upon the selected predictive mode ofoperation.

As noted above with respect to the exemplary two-mode methods, themethods described herein are applicable to collecting temperatures of asubject and estimating the temperature of a subject. As would beunderstood by one skilled in the art, these methods are readilyapplicable to collecting temperatures of a patient and other subjects,such as animals, test apparatus, and other devices requiringmeasurement, without departing from the scope of embodiments of theinvention.

Although embodiments of the invention have been described herein for usein the healthcare field, it will be appreciated that application of thepresent invention is not limited to the health care field. Embodimentsof the invention may be used anywhere that fast response electronicthermometers are useful. For example, embodiments of the presentinvention may be used in industrial temperature measurement applicationsand various laboratory applications.

When introducing elements of the present invention or the preferredembodiment(s) thereof, the articles “a”, “an”, “the” and “said” areintended to mean that there are one or more of the elements. The terms“comprising”, “including” and “having” are intended to be inclusive andmean that there may be additional elements other than the listedelements. Moreover, the use of “up”, “down”, “top” and “bottom” andvariations of these terms is made for convenience, but does not requireany particular orientation of the components.

As various changes could be made in the above without departing from thescope of the invention, it is intended that all matter contained in theabove description and shown in the accompanying drawings shall beinterpreted as illustrative and not in a limiting sense.

What is claimed is:
 1. An electronic thermometer comprising: a probeadapted to be heated by a subject for use in measuring the temperatureof the subject; at least one temperature sensor for detecting thetemperature of the probe; and a processor configured for user selectionbetween at least a first predictive mode of operation of the thermometerand a second predictive mode of operation of the thermometer fordetermining temperature, the second mode of operation determiningtemperature more slowly but with greater precision as compared with thefirst mode of operation, the first mode of operation utilizing apredictive algorithm for estimating the temperature of the subjectbefore the thermometer reaches full equilibrium with the subject basedon a plurality of samples of the temperature of the probe detected bythe temperature sensor.
 2. The electronic thermometer as set forth inclaim 1, wherein said processor is further configured for user selectionbetween at least the first mode of operation, the second mode ofoperation, and a third mode of operation of the thermometer, the thirdmode of operation comprising a direct measurement mode by collectingtemperature information until the temperature of the temperature sensorequilibrates with the subject, whereby the thermometer determines thetemperature in the third mode of operation more slowly and withoututilizing a prediction algorithm but with even greater precision, ascompared with the first and second modes of operation.
 3. The electronicthermometer as set forth in claim 1, wherein as a result of the userselection of the first mode of operation of the thermometer, theprocessor is further configured to estimate the temperature of thesubject with the predictive algorithm according to the first mode ofoperation when a predetermined number of samples of the temperature ofthe probe detected by the temperature sensor has been collected.
 4. Theelectronic thermometer as set forth in claim 1, wherein as a result ofthe user selection of the first mode of operation of the thermometer,the processor is further configured to estimate the temperature of thesubject with the predictive algorithm according to the first mode ofoperation when the samples of the temperature of the probe detected bythe temperature sensor have been collected for at least a predeterminedamount of time.
 5. The electronic thermometer as set forth in claim 1,wherein as a result of the user selection of the second mode ofoperation of the thermometer, the processor is further configured toestimate the temperature of the subject with the predictive algorithmaccording to the second mode of operation when the estimates of thepredictive algorithm converge to a precision meeting a minimumthreshold.
 6. The electronic thermometer as set forth in claim 1,wherein the processor is further configured to collect one or moreadditional samples of the temperature of the probe detected by thetemperature sensor when the estimated temperature of the subject isoutside a predetermined temperature range.
 7. The electronic thermometeras set forth in claim 1, wherein said processor is further configuredfor receiving from a user of the thermometer a selection between aplurality of predictive modes of operation of the thermometer, theplurality of predictive modes of operation being arranged for selectionalong a continuum from a shortest measurement duration and astandard-precision measurement to a longest measurement duration and ahighest-precision measurement, each of said plurality of predictivemodes of operation utilizing the same predictive algorithm forestimating the temperature of the subject before the thermometer reachesfull equilibrium with the subject.
 8. The electronic thermometer as setforth in claim 7, further comprising one of a rotary dial adapted to berotated to a plurality of positions corresponding to the plurality ofpredictive modes of operation, a movable selector adapted to be moved toa plurality of positions corresponding to the plurality of predictivemodes of operation, and a plurality of buttons, each buttoncorresponding to one of the plurality of predictive modes of operation.9. An electronic thermometer comprising: a probe adapted to be heated bya subject for use in measuring a temperature of the subject; at leastone temperature sensor for detecting the temperature of the probe; and aprocessor configured for: receiving from a user of the thermometer aselection of one of a plurality of modes of operation of thethermometer, said user selecting between at least a first mode ofoperation of the thermometer for estimating the temperature of thesubject and a second mode of operation of the thermometer for estimatingthe temperature of the subject; collecting temperatures of the subjectmeasured by the thermometer over time; applying a first portion of thecollected measured temperatures to a predictive algorithm according tothe first mode of operation when the selection received from the user isfor the first mode of operation; applying the first portion and a secondportion of the collected measured temperatures to the same predictivealgorithm according to the second mode of operation when the selectionreceived from the user is for the second mode of operation; andestimating the temperature of the subject with the predictive algorithmbased on the selected mode of operation before the thermometer reachesfull equilibrium with the subject.
 10. The electronic thermometer ofclaim 9, wherein the processor is further configured to estimate thetemperature of the subject with the predictive algorithm based on thefirst portion of collected measured temperatures according to the firstmode of operation more quickly as compared with when the temperature ofthe subject is estimated with the predictive algorithm based on thefirst portion and the second portion of collected measured temperaturesaccording to the second mode of operation.
 11. The electronicthermometer of claim 9, wherein the processor is further configured toestimate the temperature of the subject with the predictive algorithmbased on the first portion and the second portion of collected measuredtemperatures according to the second mode of operation with greaterprecision as compared with when the temperature of the subject isestimated with the predictive algorithm based on the first portion ofcollected measured temperatures according to the first mode ofoperation.
 12. The electronic thermometer of claim 9, wherein as aresult of the selection by the user of the first mode of operation ofthe thermometer, the processor is further configured to apply fewermeasured temperatures to the predictive algorithm according to the firstmode of operation as compared with the number of measured temperaturesapplied to the same predictive algorithm according to the second mode ofoperation.
 13. The electronic thermometer of claim 9, wherein as aresult of the selection by the user of the first mode of operation ofthe thermometer, the processor is further configured to estimate thetemperature of the subject with the predictive algorithm according tothe first mode of operation when the collecting temperatures of thesubject over time has collected at least a predetermined number ofmeasured temperatures.
 14. The electronic thermometer of claim 9,wherein as a result of the selection by the user of the first mode ofoperation of the thermometer, the processor is further configured toestimate the temperature of the subject with the predictive algorithmaccording to the first mode of operation when the collectingtemperatures of the subject over time has occurred continuously for atleast a predetermined amount of time.
 15. The electronic thermometer ofclaim 9, wherein as a result of the selection by the user of the secondmode of operation of the thermometer, the processor is furtherconfigured to estimate the temperature of the subject with thepredictive algorithm according to the second mode of operation when theestimates of the predictive algorithm converge to a precision meeting aminimum threshold.
 16. The electronic thermometer of claim 9, whereinthe processor is further configured to apply measured temperatures tothe predictive algorithm collected over less time according to the firstmode of operation as compared with the measured temperatures applied tothe same predictive algorithm according to the second mode of operation.17. The electronic thermometer of claim 9, wherein the processor isfurther configured to collect one or more additional temperatures of thesubject measured by the thermometer when the estimated temperature ofthe subject is outside a predetermined temperature range.
 18. Theelectronic thermometer of claim 9, wherein the processor is furtherconfigured for user selection between at least the first mode ofoperation, the second mode of operation, and a third mode of operationof the thermometer, the third mode of operation comprising a directmeasurement mode for collecting temperature information until thetemperature of the temperature sensor equilibrates with the subject,whereby the thermometer determines the temperature in the third mode ofoperation more slowly and without utilizing a predictive algorithm butwith greater precision, as compared with the first and second modes ofoperation.
 19. The electronic thermometer of claim 18, wherein theprocessor is further configured to: determine if a time limit haselapsed; and switch from one of the first and second modes of operationselected by the user to the direct measurement mode of operation whenthe time limit has elapsed.
 20. An electronic thermometer comprising: aprobe configured to be heated by a subject for use in measuring atemperature of the subject; a temperature sensor for detecting thetemperature of the probe; a selection element adjustable along acontinuum; and a processor configured for: receiving via the selectionelement from a user of the electronic thermometer a selection of one ofa plurality of predictive modes of operation of the thermometer, theplurality of predictive modes of operation being selectable along acontinuum from a shortest measurement duration and a standard-precisionmeasurement to a longest measurement duration and a highest-precisionmeasurement; collecting temperatures of the subject measured by thethermometer over time; applying at least some of the collected measuredtemperatures to a predictive algorithm determined according to thepredictive mode of operation selected by the user, wherein a fewernumber of the collected measured temperatures are applied to thepredictive algorithm for the standard-precision measurement than for thehighest-precision measurement; and estimating the temperature of thesubject with the predictive algorithm based upon the selected mode ofoperation.